fix: A workspace whose agent is still running sub-agents no longer shows as idle

docs/AGENTS.md

@@ -314,8 +314,12 @@ main agent's, its `AskUserQuestion` parked the workspace idle while background s
 were still working (the park then swallowing their busy signals until the next prompt),
 and any tool it tried after an idle `Stop` would trip the `PreToolUse`-while-idle rule with
 no `Stop` to follow. Only the main agent's `PreToolUse(AskUserQuestion)` parks, and only its
-`PostToolUse`/`PostToolUseFailure(AskUserQuestion)` unparks; sub-agent tool activity still
-reaches the status through `PostToolUse`. Pinned against a real TUI by the `suggestionfork`
+`PostToolUse`/`PostToolUseFailure(AskUserQuestion)` or its turn-ending `Stop` unparks;
+sub-agent tool activity still reaches the status through `PostToolUse`. The `Stop` covers a
+question Claude drops without a `PostToolUse` (a message arriving mid-tool can start a second
+turn branch that asks it, and the first branch then ends the turn): no question can outlive
+the turn, and a `Stop` that lifts a park while background tasks keep the workspace busy goes
+busy instead of leaving it parked idle. Pinned against a real TUI by the `suggestionfork`
 scenario in `claude/server-manager.boundary.test.ts`.
 
 ### Busy→Idle Edge for Untracked Turns (Claude Code)

src/modules/agent-module/claude/server-manager.integration.test.ts

@@ -2405,6 +2405,37 @@ describe("ClaudeCodeServerManager integration", () => {
       expect(statusChanges).toEqual(["idle", "busy", "idle", "busy"]);
     });
 
+    it("the main agent's Stop lifts a dropped AskUserQuestion park while sub-agents run", async () => {
+      // Real trace: a message arriving mid-tool started a second turn branch that
+      // asked a question; the first branch then ended the turn and the question
+      // vanished with no PostToolUse. The Stop must unpark, and the still-running
+      // sub-agents keep the workspace busy instead of their activity being
+      // suppressed to idle.
+      const { port, statusChanges } = await start();
+      await sendHook(port, "PreToolUse", { workspacePath: WS, tool_name: "AskUserQuestion" });
+      expect(lastStatus(statusChanges)).toBe("idle");
+
+      await sendHook(port, "Stop", stopWith([subagentTask()]));
+      expect(lastStatus(statusChanges)).toBe("busy");
+
+      // The idle_prompt echo stays suppressed; the sub-agents' end still goes idle.
+      await sendHook(port, "Notification", { workspacePath: WS, notification_type: "idle_prompt" });
+      await sendHook(port, "UserPromptSubmit", { workspacePath: WS });
+      await sendHook(port, "Stop", stopWith([]));
+      expect(statusChanges).toEqual(["idle", "busy", "idle", "busy", "idle"]);
+    });
+
+    it("the main agent's Stop lifts a dropped park with nothing running (stays idle)", async () => {
+      const { port, statusChanges } = await start();
+      await sendHook(port, "PreToolUse", { workspacePath: WS, tool_name: "AskUserQuestion" });
+      await sendHook(port, "Stop", stopWith([]));
+      expect(lastStatus(statusChanges)).toBe("idle");
+
+      // No park is left behind: a later sub-agent-free tool call is not suppressed.
+      await sendHook(port, "PreToolUse", { workspacePath: WS, tool_name: "Bash" });
+      expect(lastStatus(statusChanges)).toBe("busy");
+    });
+
     it("Stop without sub-agents still transitions to idle normally", async () => {
       const port = await serverManager.startServer(testPath("/workspace/feature-a").toNative(), {
         workspaceRef: refOf(testPath("/workspace/feature-a").toNative()),

src/modules/agent-module/claude/server-manager.ts

@@ -1124,12 +1124,22 @@ export class ClaudeCodeServerManager implements AgentServerManager {
     // auth, max-tokens — and the payload omits the field), so it always goes idle
     // to surface the stuck main agent regardless of background work; clear the
     // stash there.
+    //
+    // The main agent's Stop also ends any AskUserQuestion park: its turn is over,
+    // so no question of its own can still be open. Claude can drop a question
+    // without a PostToolUse (seen when a message arriving mid-tool started a
+    // second turn branch that asked it, and the first branch then ended the
+    // turn), and a park left behind would suppress every busy signal from the
+    // still-running background tasks. So a Stop that lifts a park while tasks
+    // keep the workspace busy goes busy rather than staying parked idle.
     if (hookName === "Stop") {
       const tasks = Array.isArray(payload.background_tasks) ? payload.background_tasks : [];
       const busyTasks = tasks.filter((task) => taskKeepsBusy(task));
+      const wasParked = state.awaitingUserInputResolution === true;
+      state.awaitingUserInputResolution = false;
       state.busyForBackgroundTasks = busyTasks.length > 0;
       if (busyTasks.length > 0) {
-        newStatus = null;
+        newStatus = wasParked ? "busy" : null;
         this.logger.scoped({ path: normalizedPath }).debug("Idle suppressed for background tasks", {
           tasks: busyTasks.map((task) => task.command ?? task.agent_type ?? task.type).join(", "),
         });